A High Order Bound Preserving Finite Difference Linear Scheme for Incompressible Flows

We propose a high order finite difference linear scheme combined with a high order bound preserving maximum-principle-preserving (MPP) flux limiter to solve the incompressible flow system. For such problem with highly oscillatory structure but not strong shocks, our approach seems to be less dissipative and much less costly than a WENO type scheme, and has high resolution due to a Hermite reconstruction. Spurious numerical oscillations can be controlled by the weak MPP flux limiter. Numerical tests are performed for the Vlasov-Poisson system, the 2D guiding-center model and the incompressible Euler system. The comparison between the linear and WENO type schemes, with and without the MPP flux limiter, will demonstrate the good performance of our proposed approach.     

Effect of gender on the reliability of COVID-19 rapid antigen test among elderly

Defining con-founders that affect the reliability of diagnostic tests for coronavirus disease 2019 is vital to breaking the chain of infection. The elderly population is a higher risk group for the emerging virus. However, gender seems to exert a critical role in modifying the infection risk among women owing to hormonal changes. The menopause transition is an exceptional period for older women where the protective and immunomodulatory effects of the estrogen hormone are lost. Accordingly, attention should be given to postmenopausal women since they will have an increased risk compared to their pre-menopausal peers.     

Atrial fibrillation after cardiac surgery: A systematic review and meta-analysis

ObjectiveNew-onset postoperative atrial fibrillation (POAF) after cardiac surgery is common, with rates up to 60%. POAF has been associated with early and late stroke, but its association with other cardiovascular outcomes is less known. The objective was to perform a meta-analysis of the studies reporting the association of POAF with perioperative and long-term outcomes in patients with cardiac surgery.MethodsWe performed a systematic review and a meta-analysis of studies that presented outcomes for cardiac surgery on the basis of the presence or absence of POAF. MEDLINE, EMBASE, and the Cochrane Library were assessed; 57 studies (246,340 patients) were selected. Perioperative mortality was the primary outcome. Inverse variance method and random model were performed. Leave-one-out analysis, subgroup analyses, and metaregression were conducted.ResultsPOAF was associated with perioperative mortality (odds ratio [OR], 1.92; 95% confidence interval [CI], 1.58-2.33), perioperative stroke (OR, 2.17; 95% CI, 1.90-2.49), perioperative myocardial infarction (OR, 1.28; 95% CI, 1.06-1.54), perioperative acute renal failure (OR, 2.74; 95% CI, 2.42-3.11), hospital (standardized mean difference, 0.80; 95% CI, 0.53-1.07) and intensive care unit stay (standardized mean difference, 0.55; 95% CI, 0.24-0.86), long-term mortality (incidence rate ratio [IRR], 1.54; 95% CI, 1.40-1.69), long-term stroke (IRR, 1.33; 95% CI, 1.21-1.46), and longstanding persistent atrial fibrillation (IRR, 4.73; 95% CI, 3.36-6.66).ConclusionsThe results suggest that POAF after cardiac surgery is associated with an increased occurrence of most short- and long-term cardiovascular adverse events. However, the causality of this association remains to be established.     

The effect of massage therapy on pain after surgery: A comprehensive meta-analysis

BackgroundFindings on the usefulness of massage therapy (MT) in postoperative pain management are often inconsistent among studies.ObjectivesThis study’s aim is to conduct a meta-analysis of randomized controlled trials (RCT) to clarify the effects of massage therapy in the treatment of postoperative pain.MethodsThree databases (PubMed, Embase, and Cochrane Central Register of Controlled Trials) were searched for RCTs published from database inception through January 26, 2021. The primary outcome was pain relief. The quality of RCTs was appraised with the Cochrane Collaboration risk of bias tool. The random-effect model was used to calculate the effect sizes and standardized mean difference (SMD) with 95 % confidential intervals (CIs) as a summary effect. The heterogeneity test was conducted through I². Subgroup and sensitivity analyses were used to explore the source of heterogeneity. Possible publication bias was assessed using visual inspection of funnel plot asymmetry.ResultsThe analysis included 33 RCTs and showed that MT is effective in reducing postoperative pain (SMD, −1.32; 95 % CI, −2.01 to −0.63; p = 0.0002; I² = 98.67 %). A similar significant effect was found for both short (immediate assessment) and long terms (assessment performed 4–6 weeks after the MT). Remarkably, we found neither the duration per session nor the dose had an impact on the effect of MT and there seemed to be no difference in the effects of different MT types. In addition, MT seemed to be more effective for adults. Furthermore, MT had better analgesic effects on cesarean section and heart surgery than orthopedic surgery.LimitationsPublication bias is possible due to the inclusion of studies in English only. Additionally, the included studies were extremely heterogeneous. Double-blind research on MT is difficult to implement, and none of the included studies is double-blind. There was some heterogeneity and publication bias in the included studies. In addition, there is no uniform evaluation standard for the operation level of massage practitioners, which may lead to research implementation bias.ConclusionsMT is effective in reducing postoperative pain in both short and long terms.     

Minimally Invasive Treatments for Benign Prostatic Hyperplasia: Systematic Review and Network Meta-Analysis

PurposeTo review and to compare indirectly the outcomes of minimally invasive therapies for the treatment of lower urinary tract symptoms secondary to benign prostatic hyperplasia.Materials and MethodsA literature search via Medline and Cochrane Central databases was completed for randomized control studies published between January 2000 to April 2020 for the following therapies: Rezum, Urolift, Aquablation, and prostatic artery embolization (PAE). Data on the following variables were included: International prostate symptom score (IPSS), maximum urinary flow rate, quality of life, and postvoid residual (PVR). Standard mean differences between treatments were compared through a meta-analysis using transurethral resection of the prostate (TURP) to assess differences in treatment effect.ResultsThere was no significant difference in outcomes between therapies for IPSS at the 3, 6, and 12-month follow ups. Although outcomes for Rezum were only available out to 3 months, there were no consistently significant differences in outcomes when comparing Aquablation versus PAE versus Rezum. TURP PVR was significantly better than Urolift at 3, 6, and 12 months. No significant differences in minor or major adverse events were noted.ConclusionAlthough significant differences in outcomes were limited, Aquablation and PAE were the most durable at 12 months. PAE has been well studied on multiple randomized control trials with minimal adverse events while Aquablation has limited high quality data and has been associated with bleeding-related complications.     

Comparison between Antegrade versus Retrograde Ureteral Stent Placement for Malignant Ureteral Obstruction

PurposeTo compare the technical success of antegrade uteral stent (AUS) and retrograde ureteral stent (RUS) placements in patients with malignant ureteral obstruction (MUO) and to determine the predictors of technical failure of RUS.Materials and MethodsThis study retrospectively included 61 AUS placements (44 patients) performed under fluoroscopic guidance and 76 RUS placements (55 patients) performed under cystoscopic guidance in patients with MUO from January 2019 to December 2020. Technical success rates of the 2 techniques were compared using inverse probability of treatment weighting (IPTW) analysis. Logistic regression was used to identify predictive factors for technical failures.ResultsTechnical success was achieved in 98.4% of the AUS group and 47.4% of the RUS group. After stabilized IPTW, the technical success rate was higher in the AUS group than in the RUS group (adjusted risk difference, 49.4%; 95% confidence interval [CI], 35.4%–63.1%). The independent predictors for technical failure of the RUS procedure were age of ≥65 years (odds ratio [OR], 5.56; 95% CI, 1.73–21.27), ureteral orifice invasion (OR, 4.21; 95% CI, 1.46–13.46), and extrinsic cancer (OR, 15.58; 95% CI, 2.92–111.81).ConclusionsThe technical success rate of AUS placement was higher than that of RUS placement in patients with MUO. RUS failure was associated with age of ≥65 years, cancer with ureteral orifice invasion, and extrinsic ureteral obstruction.     

两种不同放疗技术治疗鼻咽癌的疗效及计量学差异比较

目的:分析探讨两种不同放疗技术治疗鼻咽癌的疗效及计量学差异。方法:选取我院于2016年4月至2019年4月期间收治的63例鼻咽癌患者，根据鼻咽癌2008分期，其中T4期鼻咽癌患者有21例，T3期鼻咽癌患者有21例，T1-2期鼻咽癌患者有21例；所有入选患者均根据其具体情况制定固定野IMRT计划和旋转容积调强放疗计划，分别比较各期患者两套计划的计量学参数；分析两套计划的治疗时间和跳数、危及器官剂量、靶区覆盖等差异。结果:两种不同放疗技术均具备较好的靶区剂量分布，其中PTV1和PGTV的适行性和均匀性相当，两者剂量分布差异并没有统计学意义（均P>0.05）。IMRT组的PTV2剂量显著高于RapidArc组，并且前者的均匀性显著优于后者（均P<0.05），但是RapidArc组的剂量分布也能够满足临床需要。在按照患者T分期进行分层比较时，T3期患者和T1-2期患者的两种不同放疗技术靶区剂量分布相似，并且适形性和均匀性均相当。对于T4期患者而言，RapidArc组的PTV2、PTV1、PGTV靶区剂量均显著高于IMRT组（均P<0.05）；RapidArc组T4期患者的PGVT均匀指数优于IMRT组，两组数据比较差异虽无统计学意义（P=0.059），但P值接近0.05。RapidArc组治疗时间和治疗跳数分别为（185.92±32.19）s和（651.29±112.20）MUs，分别低于IMRT组的（522.29±73.39）s和（1 891.28±253.39）MUs，两组数据比较差异具有统计学意义（t=13.283，t=22.192，均P<0.05）。结论:对鼻咽癌患者采用9野IMRT和RapidArc治疗均能够达到临床要求，但是后者的治疗时间和治疗跳数更短，可以显著降低正常器官的剂量，在T4期鼻咽癌患者的治疗方面可以将高剂量区集中在靶区，从而大大减少正常器官的受照剂量，值得在临床上加以推广运用。     

Gender,power and intimate relationships over the life course among Ethiopian female peer educators living with HIV

Historically, Ethiopian women have faced numerous challenges to gender equity at the individual, relational and community levels; such inequalities can lead to increased risk of HIV acquisition. Over the past two decades, some progress has been made towards changing policies and norms to reduce gender inequality. We sought to understand the ways in which marriage and other romantic/sexual relationships of a group of Ethiopian women living with HIV had been impacted by gender norms, relational power dynamics and HIV status over the life course. We conducted in-depth interviews with 19 women living with HIV who were working as peer educators at a large clinic in Addis Ababa, Ethiopia. Reflecting on their early lives, participants often described traumatic prior relationships characterised by rape, forced marriage and HIV nondisclosure. In the aftermath of being diagnosed with HIV, participants’ more recent relationships embodied a more egalitarian dynamic characterised by mutual support for HIV care engagement and open communication. Participants’ narratives illustrate encouraging examples of ways in which HIV-positive women can form and maintain equitable and satisfying personal relationships even in the context of obstacles at multiple levels.     

Disparities in Stage at Diagnosis in an Equal-access Integrated Delivery System: A Retrospective Cohort Study of 7244 Patients With Bladder Cancer

BackgroundDisparities in bladder cancer survival by race/ethnicity and gender are likely related to differences in diagnosis. We assessed disparities in stage at diagnosis and potential contributing factors within a large, integrated delivery system.Patients and MethodsWe conducted a retrospective cohort study of 7244 patients with bladder cancer age ≥ 21 years diagnosed from January 2001 to June 2015 within Kaiser Permanente Southern California. Bivariate analyses compared stage at diagnosis – as well as comorbidities, health plan membership length, and health care utilization prior to diagnosis – by race/ethnicity, gender, and age. Multivariable generalized linear mixed models with urologist as a random effect were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for diagnosis of muscle-invasive bladder cancer (MIBC) versus non–muscle-invasive bladder cancer.ResultsIn multivariable analyses, stage at diagnosis varied significantly by race/ethnicity (P < .001). Non-Hispanic black patients had significantly higher odds of being diagnosed with MIBC than non-Hispanic white patients (OR, 1.33; 95% CI, 1.05-1.67), whereas Asian patients had significantly lower odds (OR, 0.67; 95% CI, 0.49-0.91). Women were significantly more likely to be diagnosed with MIBC than men (OR, 1.40; 95% CI, 1.22-1.61). Non-Hispanic black women had the highest proportion (39%) of MIBC diagnoses. Among Hispanic and Asian patients, a greater proportion of diagnoses occurred at younger ages.ConclusionsHealth care coverage within an equal-access system did not eliminate disparities in stage at diagnosis by race/ethnicity or gender. Studies are needed to identify etiologic factors and aspects of care delivery (eg, patient-physician interactions) that may affect the diagnostic process to inform efforts to improve health equity.